Anvil assembly delivery system

ABSTRACT

An anvil assembly suitable for trans-oral delivery is provided. The anvil assembly includes a housing configured to receive a guide suture that is severed during a stapling procedure. An anvil delivery assembly including the anvil assembly and a suture guide assembly secured to the anvil assembly is also provided.

BACKGROUND

1. Technical Field

The present disclosure relates to an anvil assembly for use with asurgical stapling device. More particularly, the present disclosurerelates to an anvil assembly for trans-oral delivery of the anvilassembly.

2. Background of Related Art

Trans-oral delivery systems for delivering an anvil assembly to asurgical site, e.g., the stomach, are known. In known delivery systems,a guide suture is threaded through one or more openings in the head ofthe anvil assembly to facilitate trans-oral insertion of the anvilassembly. The guide suture may be used to dislodge the anvil assembly ifit becomes stuck within a body lumen during trans-oral delivery and/orto retrieve the anvil assembly in the event of an emergency, e.g.,cardiac arrest. Improved methods for securing the guide suture to ananvil assembly to facilitate detachment of the guide suture from theanvil assembly once the anvil assembly is delivered to the surgical siteand/or the stapling procedure has been performed is desirable.

SUMMARY

An anvil assembly for a surgical stapling device is provided. The anvilassembly includes an anvil center rod and a head assembly pivotallysecured to the anvil center rod about a pivot axis. The head assembly ismovable between an operative position and a tilted position. The headassembly includes a housing and cutting member supported within thehousing. The housing includes an inner surface defining first and secondopenings for receiving a suture therethrough. The cutting memberincludes a knife engageable with the inner surface of the housingbetween the first and second openings to sever the suture. The innersurface may further include a recess formed between the first and secondopenings. In embodiments, the recess and the knife may be annular. Thecutting member is movable from a first position spaced from the innersurface of the housing to a second position in contact with the innersurface of the housing.

In embodiments, the head assembly may further include a retainer memberhaving an annular body portion and a frangible ring for maintaining thecutting member in the first position. Separation of the frangible ringfrom the annular body portion may permit movement of the cutting memberfrom the first position to the second position. The anvil assembly mayfurther include a biasing member positioned to urge the head assemblyrelative to the anvil center rod to position the head assembly in thetilted position.

Also provided is an anvil delivery system. The anvil delivery systemincludes an anvil assembly and a suture guide assembly. The suture guideassembly includes a guide suture secured to the head assembly and a reelassembly configured for selectively dispensing the guide suture. Theguide suture may be received through the first opening in the housingand extend from the second opening in the housing. The reel assembly mayinclude a reel housing and a reel member rotatably received within thereel housing. The guide suture may be supported about the reel member.The reel member may define an annular channel for receiving the guidesuture. The reel member may be rotatably supported on the reel housingwithin an annular cavity in the housing.

In embodiments, the anvil delivery system further includes a tubularguide assembly for trans-oral insertion of the anvil assembly. Thetubular guide assembly may include a flexible tube and an adapterconfigured for operably connecting the flexible tube to the anvil centerrod. The tubular guide assembly may further include a retaining suturefor retaining the head assembly of the anvil assembly in the tiltedposition. The retaining suture may be received through third and fourthopenings in the housing and is secured between the adapter and theflexible tube.

In addition, a kit for performing a surgical stapling procedure isprovided. The kit includes an anvil assembly, a suture guide, and atubular guide assembly. The suture guide assembly may include a guidesuture and a reel assembly. The tubular guide assembly may include aflexible tube and an adapter.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments of the presently disclosed anvil assembly and anvilassembly delivery system are disclosed herein with reference to thedrawings wherein:

FIG. 1 is a perspective view of a surgical stapling device including anembodiment of an anvil assembly according to the present disclosure;

FIG. 2 is a perspective side view of the anvil assembly of FIG. 1 fromthe distal end;

FIG. 3 is a perspective side view of the anvil assembly shown in FIGS. 1and 2 from the proximal end;

FIG. 4 is an exploded side, perspective view of the anvil assembly ofFIGS. 1-3;

FIG. 5 is a distal end view of the anvil assembly of FIGS. 1-4;

FIG. 6 is a side cross-sectional view taken along section line 6-6 ofFIG. 5;

FIG. 7 is a side cross-sectional view taken along section line 7-7 ofFIG. 5;

FIG. 8 is an enlarged side view of a cam latch member of the anvilassembly of FIGS. 1-7;

FIG. 9 is a top view of the anvil assembly of FIGS. 1-7 engaged with ananvil delivery system;

FIG. 10 is an enlarged exploded view of the anvil delivery system ofFIG. 9;

FIG. 11 an enlarged top view of the anvil delivery system of FIGS. 9 and10, engaged with the anvil assembly of FIGS. 1-7;

FIG. 12 is a side cross-sectional view taken along section line 12-12 ofFIG. 11;

FIG. 13 is a side cross sectional view of the anvil assembly of FIGS.1-7, in a pre-fired tilted position, engaged with the anvil deliverysystem of FIGS. 9-12;

FIG. 14 is an enlarged view of the indicated area of detail shown inFIG. 13;

FIG. 15 is an illustration of the anvil assembly and anvil deliverysystem of FIGS. 11 and 12 being inserted trans-orally into a patient;

FIG. 16 is an enlarged side view of the distal head portion of thesurgical stapling device of FIG. 1 with the anvil assembly removed;

FIG. 17 is an enlarged side view of the distal head portion of thesurgical stapling device of FIG. 1 with the anvil assembly of FIGS. 1-7received thereon;

FIG. 18 is an enlarged side cross-sectional view of the distal headportion of the surgical stapling device of FIG. 1 and the anvil assemblyof FIGS. 1-7 in a pre-fired non-tilted operative position;

FIG. 19 is an enlarged side cross-sectional view of the distal headportion of the surgical stapling device of FIG. 1 and the anvil assemblyof FIGS. 1-7 in a post-fired non-titled operative position;

FIG. 20 is an enlarged side cross-sectional view of the distal end ofthe anvil assembly of FIGS. 1-7 in the post-fired operative position;

FIG. 21 is an enlarged side cross-sectional view of the distal end ofthe anvil assembly of FIGS. 1-7 in a post-fired tilted position;

FIG. 22 is a side cross-sectional view of the anvil assembly of FIGS.1-7 in a post-fired tilted position supported on an anvil retainer ofthe surgical instrument of FIG. 1;

FIG. 22A is another side cross-sectional view of the anvil assembly ofFIGS. 1-7 in a post-fired tilted position supported on an anvil retainerof the surgical instrument of FIG. 1

FIG. 23 is an enlarged view of the indicated area of detail shown inFIG. 22A;

FIG. 24 is a side view of the anvil assembly of FIG. 22 supported on theanvil retainer of the surgical stapling device of FIG. 1 in thepost-fired tilted position;

FIG. 25 is a side perspective view of an anvil assembly according toanother embodiment of the present disclosure in the operative position;

FIG. 26 is a side perspective view of the anvil assembly of FIG. 25 inthe first tilted position;

FIG. 27 is an exploded perspective view of the anvil assembly of FIG.25;

FIG. 28 is a bottom perspective view of a housing of the anvil assemblyof FIG. 25;

FIG. 28A is an end view of the housing of the anvil assembly of FIG. 25from a proximal end;

FIG. 29 is a bottom perspective view of a head assembly of the anvilassembly of FIG. 25;

FIG. 30 is a top perspective view of the anvil assembly of FIG. 25 withthe housing of FIG. 28 removed;

FIG. 31 is a bottom perspective view of a backup member/cutting ringassembly of the anvil assembly of FIG. 25;

FIG. 32 is a side cross-sectional view of the anvil assembly of FIG. 25in the operative position with the backup member/cutting ring assemblyin a first or proximal position; and

FIG. 33 is a side cross-sectional view of the anvil assembly of FIG. 25in the operative position with the backup member/cutting ring assemblyin a second or distal position.

DETAILED DESCRIPTION OF EMBODIMENTS

Embodiments of the presently disclosed anvil assembly delivery systemwill now be described in detail with reference to the drawings in whichlike reference numerals designate identical or corresponding elements ineach of the several views. Throughout this description, the term“proximal” will refer to the portion of the instrument closest to theoperator and the term “distal” will refer to the portion of theinstrument furthest from the operator.

FIG. 1 illustrates an embodiment of a surgical stapling deviceconfigured for use with tilt anvil assemblies according to the presentdisclosure. Briefly, surgical stapling device 10 includes a proximalhandle assembly 12, an elongated central body portion 14 including acurved elongated outer tube 14 a, and a distal head portion 16.Alternately, in some surgical procedures, e.g., the treatment ofhemorrhoids, it is desirable to have a substantially straight,shortened, central body portion. The length, shape and/or the diameterof body portion 14 and distal head portion 16 may also be varied to suita particular surgical procedure.

With reference still to FIG. 1, handle assembly 12 includes a stationaryhandle 18, a firing trigger 20, a rotatable approximation knob 22 and anindicator 24. A pivotally mounted trigger lock 26 is fastened to handleassembly 12 and is manually positioned to prevent inadvertent firing ofstapling device 10. Indicator 24 is positioned on the stationary handle18 and includes indicia, e.g., color coding, alpha-numeric labeling,etc., to identify to a surgeon whether the device is approximated and isready to be fired. Head portion 16 includes an anvil assembly 110 and ashell assembly 31. For a more detailed discussion of surgical stapler10, please refer to commonly owned U.S. Pat. No. 7,364,060 to Milliman,the contents of which is incorporated herein by reference in itsentirety.

Referring now to FIGS. 2-7, an anvil assembly according to an embodimentof the present disclosure is shown generally as anvil assembly 110.Anvil assembly 110 is shown in a non-titled position or operativeposition. Anvil assembly 110 includes a head assembly 112 and a centerrod assembly 114. Head assembly 112 includes a post 116, a housing 118,a backup member or plate 120, a cutting ring 122, a cutting ring cover123, an anvil plate 124, a spacer or washer 125, a cam latch member 126,and a retainer member 127. Post 116 is monolithically formed with andcentrally positioned within housing 118. Alternately, housing 118 andpost 116 may be formed separately and fastened together using a knownfastening technique, e.g., welding.

As will be discussed in further detail below, housing 118 includesopenings 119 a, 119 b sized and dimensioned to receive one or moresutures “S”. During use, a first suture “S₁” (FIG. 9) is insertedthrough openings 119a and is used to retain head assembly 112 in aretracted or first tilted position (FIG. 9) during insertion of anvilassembly 110 within a patient. A second suture “S₂” (FIG. 9) is insertedthrough openings 119 b and is configured to permit retrieval of tiltanvil assembly 110 from within a patient. During trans-oral insertion ofanvil assembly 110, suture “S₂” extends from the mouth of patient,permitting the anvil assembly 110 to be retrieved trans-orally.

With reference still to FIGS. 2-7, anvil plate 124 is supported in anouter annular recess 128 of housing 118 and includes a plurality ofstaple deforming pockets 130 for receiving and deforming staples. Atleast one tab 124 a extends radially outwardly from anvil plate 124 andis received within a cutout 132 formed in an outer rim of housing 118.Tab 124 a and cutout 132 function to align or properly position anvilplate 124 within annular recess 128 of housing 118.

With particular reference to FIGS. 6 and 7, head assembly 112 will bedescribed in detail. Backup plate 120 includes a central opening 134which is positioned about post 116 within an inner annular recess 136 ofhousing 118 between post 116 and outer annular recess 128. Backup plate120 includes a raised platform 120 a. Cutting ring 122 includes anopening 122 a having a configuration substantially the same as platform120 a. Although platform 120 a is illustrated as having a circularshape, other configurations are envisioned, e.g., square, rectangular,triangular, etc. In one embodiment, cutting ring 122 is formed frompolyethylene and is fixedly secured to backup plate 120 using, forexample, an adhesive, to form a backup plate/cutting ring assembly.Backup plate 120 is formed from a hard material, e.g., a metal.Alternately other materials of construction may be used to constructbackup plate 120 and cutting ring 122. Further, backup plate 120 andcutting ring 122, in the alternative, can be formed as a single orunitary structure.

Still referring to FIGS. 6 and 7, a cutting ring cover 123 is secured toan outwardly facing or proximal surface of cutting ring 122 using, forexample, an adhesive. In one embodiment, cutting ring cover 123 isformed from a material or materials, which have a hardness greater thanthat of the cutting ring, e.g., mylar. In one embodiment, cutting ringcover 123 includes two layers of mylar (not shown) which are joinedtogether using an adhesive and a polypropylene coating. Alternately,cutting ring 122 need not have a cover. Cutting ring 122 and backupplate 120 are slidably mounted about post 116. Backup plate 120 includesa pair of inwardly extending fingers 138 which will be described infurther detail below.

With reference still to FIGS. 6 and 7, retainer member 127 is positionedin inner annular recess 136 between backup plate 120 and a back wall 118a of housing 118. In one embodiment, retainer member 127 is annular andincludes a plurality of deformable tabs 127 a which engage a rearsurface of backup plate 120. Retainer member 127 prevents backup plate120 and cutting ring 122 from moving or being pushed into inner annularrecess 136 of housing 118 until a predetermined force sufficient todeform tabs 127 a has been applied to the backup plate/cutting ringassembly. The predetermined force can be close to but is less than theforce applied by an annular cutting blade of a surgical stapling devicewhen it engages, for example, the cutting ring of anvil assembly 110. Inone embodiment by way of example, the predetermined force is betweenabout ten pounds and about ninety pounds and can be about thirty (30)pounds. When the predetermined force is reached, e.g., during cutting oftissue, backup plate 120 is urged into inner annular recess 136 andcompresses retainer member 127. It is envisioned that other crushable,deformable, collapsible or movement restricting members may be used toretain the backup plate/cutting ring assembly in a fixed position untila predetermined force has been applied to the backup plate/cutting ringassembly.

Turning back to FIG. 4, anvil center rod assembly 114 includes a centerrod 152, a plunger 154 and plunger spring 156. A first end of center rod152 includes a pair of arms 159 which define a cavity 159 a. Each arm159 has a transverse throughbore 158 which is aligned with a centrallongitudinal axis of center rod 152. Alternately, throughbores 158 canbe offset from the longitudinal axis of center rod 152. Post 116 of headassembly 112 is dimensioned to be positioned within cavity 159 a andalso includes a transverse throughbore (not shown). A pivot member 162pivotally secures post 116 to center rod 152 via the through bores suchthat head assembly 112 may be pivotally mounted to anvil center rodassembly 114.

Turning briefly to FIG. 8, cam latch member 126 includes a body 126 ahaving a throughbore 126 b. Throughbore 126 b is dimensioned to receivepivot member 162 such that cam latch member 126 is pivotally mountedwithin transverse slot 172 (FIG. 3) of post 116 about pivot member 162.Referring now to FIGS. 3, 6 and 7, cam latch member 126 includes a firstbody portion 126 c which extends partially from slot 172 of post 116 andis positioned to be engaged by a finger 166 of plunger 154. First bodyportion 126 c is configured such that the distance between the surfaceof first body portion 126 c and through bore 126 b increase in aclockwise direction about cam latch member 126. In this manner, plunger154 is able to move forward as cam latch member 126 rotates in aclockwise direction. Additionally, this configuration of first bodyportion 126 c permits plunger 154 to be refracted as cam latch memberrotates in a counter-clockwise direction. Cam latch member 126 alsoincludes an edge 126 f, including a tab 126 b. A leading portion of edge126 f is configured to be urged into engagement with an inner periphery120 b of backup plate 120 by an engagement finger 166 of plunger 154when anvil head 112 is in its non-tilted or operative position. Tab 126g is configured to engage backwall 118 a of housing 118 to prevent camlatch member 126 from rotating counter-clockwise relative to housing118.

With reference to FIG. 6, plunger 154 is slidably positioned in a bore164 formed in the first end of center rod 152. Plunger 154 includes anengagement finger 166 which is offset from the pivot axis of headassembly 112 and biased into engagement with an edge 126 c of cam latch126. Engagement of finger 166 with edge 126 c of cam latch 126 presses aleading portion of edge 126 f against an inner periphery of back plate120 to urge head assembly 112 to an operative or non-tilted position oncenter rod 152.

Turning to FIG. 7, in the pre-fired operative position of head assembly112, i.e. when head assembly 112 has been pivoted to its non-tiltedposition, fingers 138 formed on backup plate 120 engage protrusions 152b adjacent top surface 152 a of center rod 152 to prevent head assembly112 from pivoting about pivot member 162. Head assembly 112 may betilted a degrees (FIG. 13) relative to anvil center rod assembly 114 inthe pre-fired tilted position. In one embodiment, head assembly 112 istilted about seventy degrees (70°) in its pre-fired tilted position;however it should be understood that tilting head assembly 112 to otherdegrees is also contemplated. Titling of head assembly 112 relative toanvil center rod assembly 114 causes body portion 126 c of cam latchmember 126 to engage finger 166 of plunger 154. As cam latch assembly126 rotates with the tilting of head assembly 112, plunger 154 isretracted with bore 164 of anvil center rod assembly 114, therebycompressing spring 156. In this manner, finger 166 of plunger 154 isdistally biased against body portion 126 c of cam latch member 126.

With reference to FIGS. 3 and 4, a second end of center rod 152 includesa bore 180 defined by a plurality of flexible arms 182. Flexible arms182 each include an opening 182 a dimensioned to receive a projectionformed on or connected to a shell assembly 31 (FIG. 18). Alternatively,openings 182 a may be configured to receive a suture for permittingretrieval of anvil assembly 110. The proximal ends of each of theflexible arms 182 include an internal shoulder 184 dimensioned toreleasably engage shell assembly 31 of surgical stapling device 10 tosecure anvil assembly 110 to the surgical stapling device. A pluralityof splines 186 are formed about center rod 152. Splines 186 function toalign anvil assembly 110 with the staple holding portion of a surgicalstapling device. Center rod 152 also includes an annular recessedportion 190 to facilitate grasping of anvil assembly 110 by a surgeonwith a grasper. Recessed portion 190 may include a roughened or knurledsurface or an overmold to facilitate grasping of anvil assembly 110.

With reference now to FIGS. 9-12, a system for delivering anvil assembly110 within a patient is shown generally as anvil delivery system 50.Anvil delivery system 50 includes a flexible tube 52 and an adapter 62.Flexible tube 52 includes an open end 52 a. Adapter 62 and anvilassembly 110 are supported on open end 52 a of flexible tube 52. Openend 52 a of flexible tube 52 includes a through bore 53 extendingtherethrough configured to receive a locking pin 54. Open end 52 afurther includes an opening 55. Closed end 52 b of flexible tube 52 isconfigured for trans-orally receipt in a patient. Flexible tube 52 mayinclude markings or other gradations 56 along the length thereof toindicate to a surgeon how much of flexible tube 52 has been receivedwithin the patient during insertion and/or to indicate the length offlexible tube 52 remaining in the patient upon removal.

With particular reference to FIG. 10, adapter 62 includes a first end 62a configured to be received within open end 52 a of flexible tube 52 anda second end 62 b is configured to be received with in bore 180 formedin center rod 152 of anvil assembly 110. First end 62 a includes aseries of annular rings 64 configured to frictionally retain first end62 a of adapter 62 within open end 52 a of flexible tube 52. Second end62 b of adapter 62 includes a longitudinal guide member 66 configured tobe received between flexible arms 182 formed in center rod 152 of anvilassembly 110. In addition, second end 62 b of adapter 62 is sized toallow center rod 154 of anvil assembly 110 to freely slide into and offsecond end 62 b of adapter 62. Adapter 62 further includes a firstthrough bore 70 formed in a central hub portion 62 c as well as secondand third through bores 72, 74 formed in first end 62 a. Through bore 72is configured to align with through bore 53 formed in open end 52 a offlexible tube 52 and is sized to receive locking pin 54.

With particular reference now to FIGS. 10, 13 and 14, anvil assembly 110is supported on anvil delivery system 50. Securing anvil assembly 110 toanvil delivery system 50 requires first that suture “S₁” is threadthrough openings 119 a formed on head assembly 112 such that first andsecond ends of suture “S₁” are positioned on opposites of center rod152. Next, second end 62 b of adapter 62 is positioned within throughbore 180 of center rod 152 such that longitudinal guide 66 is receivedbetween two of arm members 182. Each of the first and second ends ofsuture “S₁” is inserted through opening 55 formed in open end 52 a offlexible member 52. Head assembly 112 is then rotated to a first tiltedposition while first and second ends of suture “S₁” are pulled throughopening 55. First end 62 a of adapter 62 is then inserted into open end52 a of flexible member. The frictional contact between annular rings 64of first end 62 a of adapter 62 and an inner surface of flexible tube 52secures adapter 62 to flexible tube 52 and prevents suture “S₁” fromloosening. It is envisioned that more than one suture may be used tosecure head assembly 112 in a pre-fired tilted position.

With reference now to FIG. 15, a method for delivering anvil assembly110 to a surgical site within a patient will be described. In onemethod, anvil assembly 110 is provided in the first tilted positionsupported on anvil delivery system 50 and ready for delivery.Alternatively, a clinician secures anvil assembly 110 to anvil deliverysystem 50 as discussed above. Once anvil assembly 110 has been securedto flexible tube 52, the surgeon inserts closed end 52 b of flexibletube 52 in the patient's mouth “M” and moves closed end 52 b along withflexible tube 52 down through esophagus “E” to a surgical site, i.e.,the stomach “St”.

After insertion, the surgeon then makes a first incision “I₁” at thesurgical site (stomach “St” as shown) to create an inner access toclosed end 52 b of flexible tube 52 and then pulls open end 52 b offlexible tube 52 through first incision “I₁”. In some procedures it maybe beneficial to pull flexible tube 52 through incision “I₁” untilcenter rod 152 of anvil assembly 110 advances through first incision“I₁”. When anvil assembly 110 is properly positioned at the surgicalsite, the surgeon releases anvil delivery system 50 from anvil assembly110 by cutting suture “S₁” and separating anvil assembly 110 from secondend 62 b of adapter 62. Flexible tube 52 (with fitting 62) may then bepulled from the body through first incision “I₁”.

Severing of suture “S₁” permits plunger 154 to extend from within bore164, thereby causing finger 166 to engage body portion 126 c of camlatch member 126. Rotation of cam latch member 126 causes edge 126 f oflatch member 126 to move into engagement with the inner periphery ofbackup plate 120, thereby urging head assembly 112 to return to anon-tilted operative position. Additionally, the distal end of staplingdevice 10 may be configured to engage finger 166 of plunger 154 as anvilassembly 110 is attached to surgical stapling device 10. In this manner,the distal end of surgical stapling device 10 urges plunger 154distally, thereby ensuring the rotation of head assembly 112 to anon-tilted position.

With particular reference to FIG. 15, in one method, a second incision“I₂” is then formed at the surgical site such that distal head portion16 of surgical stapling device 10 may be received therethrough.Alternatively, distal head portion 16 of surgical stapling device 10 maybe received through first incision “I₁” once anvil deliver system 50 hasbeen removed therefrom.

Turning briefly to FIGS. 16 and 17, anvil assembly 110 is operablyreceived on an anvil retainer 32 extending from shell assembly 31 formedon a distal end of surgical stapling device 10. Once anvil assembly 110is received on surgical stapling device 10, surgical stapling device 10operates in the manner discussed in the '060 patent.

The operation of anvil assembly 110 will now be described with referenceto FIGS. 18-23. When anvil assembly 110 is in its pre-fired non-tiltedposition, backup plate 120 is spaced from backwall 118 a of housing 118by retainer 127 and protrusions 152 b of center rod 152 engage fingers138 of backup plate 120 to prevent tilting of head assembly 112 aboutpivot member 162. Finger 166 of plunger 154 is urged by spring 156 intoengagement with body portion 126 c of cam latch member 126 to urge camlatch member 126 in a clockwise direction, about pivot member 162 suchthat edge 126 f of cam latch member 126 engages inner periphery 120 b ofbackup member 120.

The firing of surgical stapling device 10 causes a knife blade 33thereof to engage cutting ring 122 to move cutting ring 122 and backupplate 120 into annular recess 136 of housing 118 of head assembly 112.Arrows “W” in FIG. 19 indicate how cutting ring 122 and backup plate 120move as a result of the firing of surgical stapling device 10. When suchmovement occurs, deformable tabs 127 a of retainer 127 are deformedagainst backwall 118 a of housing 118 and fingers 138 of backup member120 move away from protrusions 152 b of center rod 152. Further, innerperiphery 120 b of backup plate 120 moves past edge 126 f of cam latchmember 126 such that cam latch member 126 is urged to pivot about pivotmember 162 in the direction indicated by arrow “X” in FIG. 21 by plunger154 to a position in which body portion 126 d is positioned in front ofand engages backup plate 120. Engagement of plunger 154 with cam latchmember 126 urges head assembly 112 to a second tilted position (FIGS. 22and 23). It is noted that head assembly 112 will not immediately tiltupon firing of surgical stapling device 10 because, upon firing, headassembly 112 is in an approximated position, i.e., the head assembly 112is in close alignment with shell assembly 31 of stapling device 10, and,therefore, does not provide room for head assembly 112 to pivot. Assuch, the head assembly 112 will only begin to tilt when anvil assembly110 and shell assembly 31 of surgical stapling device 10 are beingunapproximated.

As head assembly 112 pivots towards its forward or second tiltedposition, finger 166 of plunger 154 maintains surface 126 e of cam latchmember 126 in contact with backup plate 120 to prevent backup plate 120from sticking to the knife blade as the knife blade is retracted. It isnoted that curved surface 126 e of cam latch member is configured toeliminate any gap and ensure contact between surface 126 e of cam latchmember 126 and backup plate 120 to hold backup plate 120 in place duringand after the knife blade is retracted such that the cutting ring andbackup plate assembly stay in their correct position during continuedtilting of anvil assembly 112. Anvil assembly 110 is configured suchthat head assembly 112 tilts to a forward or second tilted position βdegrees (FIG. 23) relative to center rod assembly 114. In oneembodiment, head assembly 112 is tilted about seventy degrees (70°) toits second tilted position such that the total pivoting movement of theanvil from the retracted or first tilted position to the forward orsecond tilted position is about one-hundred and forty degrees (140°). Itshould, however, be noted that the tilting of head assembly 112 to otherdegrees is also contemplated.

As described above, the anvil assemblies of the present disclosure areconfigured to be delivered to a surgical site, e.g., the stomach “St”(FIG. 15), trans-orally. During trans-oral delivery of the anvilassemblies, a retaining suture, i.e., first suture “S₁”, retains thehead assembly of the anvil assembly in a first tilted position and aproximal guide suture, i.e., second suture “S₂”, includes first andsecond ends “S_(2a)”, “S_(2b)” that remain external of the patient'smouth “M” that allow the surgeon to dislodge or retrieve the anvilassembly from the patient during trans-oral delivery.

As described above and with reference to FIG. 11, second suture “S₂” isthreaded through openings 119 b in housing 118 of head assembly 112 ofanvil assembly 110. Detaching second suture “S₂” from anvil assembly 110requires pulling on first end “S_(2a)” of second suture “S₂” such thatsecond end “S_(2b)” of second suture “S₂” travels from external thepatient's mouth “M” (FIG. 15), where it is accessible by the surgeon,through the patient's mouth “M” and upper gastrointestinal (GI) tract,e.g., esophagus “E” and stomach “St” (FIG. 15) and through the openings119 b in housing 118 of head assembly 112 of anvil assembly 110 beforehaving to travel back through the upper GI tract and out the patient'smouth “M”.

With reference now to FIGS. 25-33, an anvil assembly according toalternate embodiment of the present disclosure is shown generally asanvil assembly 210. As will be described in further detail below, anvilassembly 210 is configured such that second suture “S₂” (FIG. 25) issevered during a stapling procedure to detach second suture “S₂” fromanvil assembly 210 and to permit withdrawal of the second suture “S₂”from the patient by pulling on first and second ends “S_(2a)”, “S_(2b)”of the second suture “S₂”. In this manner, the second suture “S₂” isseparated from the anvil assembly 210 and withdrawn from the patientwithout having to pull the second end “S_(2b)” of the second suture “S₂”through the body lumen (FIG. 15) of the patient, i.e., the mouth “M”,the esophagus “E”, and the stomach “St”.

With reference to FIGS. 25-27, the anvil assembly 210 is substantiallysimilar to the anvil assembly 110 described hereinabove and will only bedescribed in detail as relates to differences between the anvil assembly210 and the anvil assembly 110. The anvil assembly 210 includes a headassembly 212 and a center rod assembly 214. The head assembly 212 ispivotable relative to the center rod assembly 214 and includes a housing218, a backup member 220, a cutting ring 222, and a retainer member 224.An anvil plate 226 (FIG. 28) is supported on an outer rim 230 b (FIG.28) of the housing 218 and includes a plurality of staple deformingpockets 226 a (FIG. 28) for receiving and deforming staples (not shown).The center rod assembly 214 includes a center rod 252, a plunger 254 forengaging the head assembly 212, a plunger spring 256 for biasing theplunger 254 in a distal direction, a cam latch member 258 receivedwithin the head assembly 212, and a pivot pin 260 pivotally connectingthe head assembly 212 to the center rod 252.

Referring to FIGS. 27, 28, and 28A, the housing 218 of the head assembly212 of the anvil assembly 210 includes a center post 230 a and defines acavity 231 between the center post 230 a and the outer rim 230 b. Aninner surface 218 a of the housing 218 defines a recess 217 spacedoutward from and formed about the center post 230 a within the cavity231. A first and second pair of openings 219 a, 219 b (FIG. 25) extendthrough the inner surface 218 a of the housing 218. The first pair ofopenings 219 a receives the first suture “S₁” and the second pair ofopenings 219 b receives the second suture “S₂”. More particularly, thesecond pair of openings 219 b extends through the inner surface 218 a ofhousing 218 on either side of the recess 217 such that when the secondsuture “S₂” (FIG. 32) is received through the second pair of opening 219b, the second suture “S₂” extends across the recess 217. Although therecess 217 is shown as being annular and extending completely about thecenter post 230 a of housing 218, it is envisioned that recess 217 needonly extend a distance to facilitate passage of the second suture “S₂”and, thus, may extend only partially about the center post 230 a. Inalternative embodiments, housing 218 is formed without a recess 217 andthe second suture “S₂” is received through the second pair of openings219 b and extends directly across the inner surface 218 a of housing218.

With reference to FIG. 27-31, the backup member 220, the cutting ring222, and the retainer member 224 are received within the cavity 231(FIG. 28A) of the housing 218 about the center post 230 a of housing218. The backup member 220 is secured to the cutting ring 222 to form abackup member/cutting ring assembly 225. As shown, the backupmember/cutting ring assembly 225 is formed by overmolding the backupmember 220 to the cutting ring 222. In particular, during theovermolding of the backup member 220 to the cutting ring 222, aplurality of post 223 are formed that extend through openings 221 of thecutting ring 222 to secure the backup member 220 to the cutting ring222. Alternatively, the backup member/cutting ring assembly 225 isformed as a single component or as two components that are securedtogether using mechanical fasteners or in any other suitable manner. Thebackup member/cutting ring assembly 225 is movable within the cavity 231from a proximal position (FIG. 32) to a distal position (FIG. 33). Thebackup member/cutting ring assembly 225 is retained in the proximalposition (FIG. 32) within the cavity 231 of the housing 218 by theretainer member 224.

The retainer member 224 includes an annular body portion 224 a and afrangible ring 224 b supported on the annular body portion 224 a. Thefrangible ring 224 b maintains the backup member/cutting ring assembly225 in the proximal position until a predetermined force sufficient tofracture or separate the frangible ring 224 b from the annular bodyportion 224 a of the retainer member 224 is applied to the backupmember/cutting ring assembly 225 by an annular knife 33 (FIG. 19) ofsurgical stapling device 10 (FIG. 1). The backup member/cutting ringassembly 225 is maintained within the cavity 231 of housing 218 by aplurality of tabs 222 (FIG. 31) extending outwardly from cutting ring222 and engaging the outer rim 230 b of the housing 218.

For a detailed description of the structure and function of an exemplarybackup member/cutting ring assembly 225 and an exemplary retainer member224, please refer to commonly owned U.S. application Ser. No.14/078,766, the content of which is incorporated herein by reference inits entirety.

The backup member/cutting ring assembly 225 includes a knife 232 thatextends from a distal surface 220 a of the backup member 220 and isaligned with the recess 217 defined within the housing 218. When thebackup member 220 is secured to cutting ring 222 to form the backupmember/cutting ring assembly 225, the knife 232 extends distally beyondthe distal surface 220 a (FIG. 30) of the backup member 220 towards therecess 217. Although shown has having an annular configuration andextending from the backup member 220, it is envisioned that the knife232 may include any configuration suitable for receipt within recess 217formed in inner surface 218 a (FIG. 28) of housing 218. For example, inembodiments, the length of the knife 232 corresponds to the length ofthe recess 217 and, thus, as discussed above with regard to recess 217,need only be of a length to facilitate cutting of the second suture“S₂”. In embodiments of housing 218 without the recess 217, knife 232 isconfigured to engage the inner surface 218 a of housing 218.

With particular reference now to FIG. 32, when the head assembly 212 ofthe anvil assembly 210 is in a pre-fired condition, the backupmember/cutting ring assembly 225 and thus, the knife 232 extending fromthe backup member 220, are longitudinally spaced from the inner surface218 a of the housing 218. As noted above, the backup member/cutting ringassembly 225 is maintained in the proximal position through engagementwith the frangible ring 224 b of retainer member 224 and is retainedwithin the cavity 231 of the housing 218 through engagement of theplurality of tabs 222 a of the cutting ring 222 with the outer rim 230 bof the housing 218.

As discussed above with respect to FIG. 19, during firing of thesurgical stapling device 10, an annular knife 33 is advanced distallyfrom shell assembly 31, as indicated by arrow “w”. With reference now toFIG. 32, when the anvil assembly 210 is attached to the shell assembly31 (FIG. 19) of surgical stapling device 10 (FIG. 19), distal movementof the annular knife 33 (FIG. 19) causes the knife 33 to engage thecutting ring 222 of the backup member/cutting ring assembly 225 of thehead assembly 212. When the predetermined force required to separate orfracture the frangible ring 224 b of the retainer member 224 from theannular body portion 224 a of the retainer member 224 is applied to thefrangible ring 224 b by the knife 33, the backup member/cutting ringassembly 225 is moved distally within the cavity 231 of the housing 218about the center post 230 a. Continued force from the knife 33 causesthe backup member/cutting ring assembly 225 to move distally until thebackup member/cutting ring assembly 225 engages the inner surface 218 aof the housing 218. As the backup member/cutting ring assembly 225 ismoved distally, the knife 232 of the backup member 220 is receivedwithin the recess 217 formed in the inner surface 218 a of the housing218 causing the knife 232 to engage and sever second suture “S₂”.

Once the second suture “S₂” is severed, each half of the severed secondsuture “S₂” is independently removed trans-orally from the patient bypulling on the first and second ends “S_(2a)”, “S_(2b)” of the secondsuture “S₂”. By severing the second suture “S₂” in this manner, thesurgeon is able to disengage the second suture “S₂” from the anvilassembly 210 and directly remove each half of the second suture “S₂”from within the patient without having to pull the second end “S_(2b)”of second suture “S₂” through the openings 219 b in the anvil assembly210 and back out of a patient through the body lumen. If the secondsuture “S₂” were to be removed from the patient without severing thesuture into two halves, one end “S_(2a)”, “S_(2b)” of the second suture“S₂” would have to be pulled into the body lumen of the patient andthrough the anvil assembly 210 before being pulled back through the bodylumen.

As noted above, the second suture “S₂” facilitates placement of theanvil assembly 210 within the stomach “St” (FIG. 15) of the patient. Thesecond suture “S₂” may be used to dislodge the anvil assembly 210 if itbecomes stuck within a body lumen during trans-oral delivery and/or toretrieve the anvil assembly 210 in the event of an emergency. Since thesecond suture “S₂” remains attached to the anvil assembly 210 throughoutthe placement and attachment of the anvil assembly 210 to the surgicalstapling device 10 (FIG. 1), and until the stapling procedure iscompleted, the second suture “S₂” may be used to dislodge and/orretrieve the anvil assembly 210 at any point up to the second suture“S₂” being severed.

Persons skilled in the art will understand that the devices and methodsspecifically described herein and illustrated in the accompanyingdrawings are non-limiting exemplary embodiments. It is envisioned thatthe elements and features illustrated or described in connection withone exemplary embodiment may be combined with the elements and featuresof another without departing from the scope of the present disclosure.As well, one skilled in the art will appreciate further features andadvantages of the disclosure based on the above-described embodiments.Accordingly, the disclosure is not to be limited by what has beenparticularly shown and described, except as indicated by the appendedclaims.

What is claimed is:
 1. An anvil assembly comprising: an anvil center rod; and a head assembly pivotally secured to the anvil center rod about a pivot axis, the head assembly being movable between an operative position and a tilted position, the head assembly including an housing and cutting member supported within the housing, the housing including an inner surface defining first and second openings for receiving a suture therethrough, wherein the cutting member includes a knife engageable with the inner surface of the housing between the first and second openings to sever the suture.
 2. The anvil assembly of claim 1, wherein the inner surface further includes a recess formed between the first and second openings.
 3. The anvil assembly of claim 2, wherein the recess is annular.
 4. The anvil assembly of claim 3, wherein the knife is annular.
 5. The anvil assembly of claim 1, wherein the cutting member is movable from a first position spaced from the inner surface of the housing to a second position in contact with the inner surface of the housing.
 6. The anvil assembly of claim 5, wherein the head assembly further includes a retainer member having an annular body portion and a frangible ring for maintaining the cutting member in the first position.
 7. The anvil assembly of claim 6, wherein separation of the frangible ring from the annular body portion permits movement of the cutting member from the first position to the second position.
 8. The anvil assembly of claim 1, further including a biasing member positioned to urge the head assembly relative to the anvil center rod to position the head assembly in the tilted position.
 9. An anvil delivery system comprising: an anvil assembly as recited in claim 1; and a suture guide assembly including a guide suture secured to the head assembly and a reel assembly configured for selectively dispensing the guide suture.
 10. The anvil delivery system of claim 9, wherein the guide suture is received through the first opening in the housing and extend from the second opening in the housing.
 11. The anvil delivery system of claim 9, wherein the reel assembly includes a reel housing and a reel member rotatably received within the reel housing, wherein the guide suture is supported about the reel member.
 12. The anvil delivery system of claim 11, wherein the reel member defines an annular channel for receiving the guide suture.
 13. The anvil delivery system of claim 11, wherein the reel member is rotatably supported on the reel housing within an annular cavity in the housing.
 14. The anvil delivery system of claim 9, further including a tubular guide assembly for trans-oral insertion of the anvil assembly.
 15. The anvil delivery system of claim 14, wherein the tubular guide assembly includes a flexible tube and an adapter configured for operably connecting the flexible tube to the anvil center rod.
 16. The anvil delivery system of claim 14, wherein the tubular guide assembly further includes a retaining suture for retaining the head assembly of the anvil assembly in the tilted position.
 17. The anvil delivery system of claim 16, wherein the retaining suture is received through third and fourth openings in the housing and is secured between the adapter and the flexible tube.
 18. A kit comprising: an anvil assembly according to claim 1; a suture guide assembly including a guide suture and a reel assembly; and a tubular guide assembly including a flexible tube and an adapter. 